Acquisitions - Unaudited Pro forma Consolidated Results of Operations (Detail) - Marchi Thermal Systems Inc and Miconex S.r.o. [Member] - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 25, 2015	Dec. 26, 2014
Business Acquisition Pro Forma Information Nonrecurring Adjustment [Line Items]
Net sales	$ 490,927	$ 562,918
Net loss	$ (9,161)	$ 13,371
Basic loss per share	$ (0.29)	$ 0.43
Diluted loss per share	$ (0.29)	$ 0.42

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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